Method of training a communication system
View Patent ↗A method and system of training a communication system is disclosed. The method includes a first transceiver transmitting signals through one or more antennas of the first transceiver. A second transceiver selects a subset of a plurality of antennas of the second transceiver, wherein the selected subset provides a largest aggregate received signal power. The second transceiver transmits pilots on a subset of sub-carriers of multi-carrier signals through the selected subset of the plurality of antennas of the second transceiver. The first transceiver receives the pilots, and extracts channel knowledge from the received pilots.
1. A method of training a communication system, comprising:
a first transceiver transmitting signals through one or more antennas of the first transceiver;
a second transceiver calculating a largest aggregate received signal power based on measurements of receive powers over a plurality of antennas and multiple sub-carriers of the second transceiver;
the second transceiver selecting a subset of the plurality of antennas of the second transceiver, the selected subset providing the largest aggregate received signals power;
the second transceiver transmitting pilots on sub-carriers of OFDM signals through the selected subset of the plurality of antennas of the second transceiver;
the first transceiver receiving the pilots; and
the first transceiver extracting channel knowledge from the received pilots.
2. The method of claim 1 , further comprising:
the first transceiver preprocessing a plurality of data streams based on the channel knowledge;
the first transceiver transmitting the preprocessed plurality of data streams from the plurality of antennas of the first transceiver.
3. The method of claim 2 , wherein the plurality of data streams comprises multiples of a common data stream, and preprocessing provides beam-forming transmission of the multiples of the common data stream.
4. The method of claim 2 , wherein the plurality of data streams comprises a plurality of different data streams, and preprocessing provides spatial multiplexing transmission of the different data streams.
5. The method of claim 1 , wherein the communication system comprises a plurality of frequency sub-carriers.
6. The method of claim 5 , wherein the second transceiver transmits the pilots over all of the frequency sub-carriers.
7. The method of claim 5 , wherein the second transceiver transmits the pilots over a subset of the frequency sub-carriers.
8. The method of claim 1 , wherein the second transceiver only transmits the pilots if the largest aggregate received signal power is greater than a threshold.
9. A method of a WiMAX base station characterizing a transmission channel, comprising:
the WiMAX base station transmitting OFDM signals through one or more antennas of the base station;
a subscriber calculating a largest aggregate received signal power based on measurements of received powers over a plurality of antennas and multiple sub-carriers of the subscriber;
the subscriber selecting one of the plurality of antennas of the subscriber that provides the largest aggregate received signal power;
the subscriber transmitting pilots on sub-carriers of OFDM signals through the selected antenna of the plurality of antennas of the subscriber;
the base station receiving the pilots; and
the base station extracting channel knowledge from the pilots.
10. The method of claim 9 , wherein the channel comprises a plurality of frequency sub-carriers.
11. The method of claim 10 , wherein the subscriber transmits the pilots over all of the frequency sub-carriers.
12. The method of claim 10 , wherein the subscriber transmits the pilots over a subset of the frequency sub-carriers.
13. The method of claim 10 , wherein the subscriber only transmits the pilots if the largest aggregate received signal power is greater than a threshold.
14. A method of training a communication system, comprising:
a first transceiver transmitting signals through one or more antennas of the first transceiver;
a second transceiver calculating a largest aggregate received signal power based on measurements of receive powers over a plurality of antennas and multiple sub-carriers of the second transceiver;
the second transceiver calculating a highest quality received signal;
the second transceiver selecting a subset of the plurality of antennas of the second transceiver, the selected subset providing the highest quality received signal;
the second transceiver transmitting training signals on sub-carriers of OFDM signals through the selected subset of the plurality of antennas of the second transceiver;
the first transceiver receiving the training signals; and
the first transceiver extracting channel knowledge from the received training signals.
15. The method of claim 14 , wherein selecting the subset providing the highest receive signal quality comprises selecting the subset providing at least one of a greatest SNR, a greatest SINR, a lowest BER, a lowest PER, and lowest FER.
16. The method of claim 14 , wherein the communication system comprises a plurality of frequency sub-carriers.
17. The method of claim 16 , wherein the second transceiver transmits the training signals over all of the frequency sub-carriers.
18. The method of claim 16 , wherein the second transceiver transmits the training signals over a subset of the frequency sub-carriers.
19. The method of claim 14 , wherein the second transceiver only transmits the training signals if the largest aggregate received signal power is greater than a threshold.
20. A method of a subscriber transceiver enabling training of a communication system, comprising:
a subscriber transceiver receiving transmission signals fro ma base station;
the subscriber transceiver calculating a largest aggregate received signal power based on measurements of receive powers over a plurality of antennas and multiple sub-carriers of the second transceiver;
the subscriber transceiver selecting a subset of the plurality of antennas of the subscriber transceiver, the selected subset of antennas providing the largest aggregate received signal power;
the subscriber transceiver transmitting pilots on a subset of sub-carriers of OFDM signals through the selected subset of the plurality of antennas of the subscriber transceiver;
the base station receiving the pilots; and
the base station extracting channel knowledge from the received pilots.